The present invention relates to hooks that may be attached to cords, ropes, or webbing for trying, bundling, or securing objects. Example applications include bungee cords, tie-downs, tarp straps, cargo cords, and stretch cords (hereafter simply referred to as bungee cords, collectively, regardless of whether the cord is elastic or inelastic). A bungee cord is generally a segment of cord with a rigid hook on one or both ends. The cord may be made of any suitable material, for example rubber, polyurethane, thermoplastic, nylon, polypropylene, polyester, and so on. The hook may be made of any suitable material, for example metal and/or plastic, it may be stamped, cast, or molded, and it may have practically any shape, size, and strength.
The shank, gape, and throat of a hook determine the size and type of objects that can be grappled. For example, a hook having a shallow throat (a short bend) may have difficulty securely attaching around an object, but it may be easy to insert into a small-diameter hole. On the other hand, a hook having a deep throat (a long bend) may easily attach around an object, but at may be difficult or impossible insert into a small-diameter hole.
Many standard “S” and “C” hooks have deep throats, and are therefore not suntan for all applications. Consequently, some bungee cords have hooks that are specially shaped for certain applications. In contrast, some bungee cords have a generic fitting in place of a hook so that any hook that has a complementary fitting can be connected to the cord.
Sometimes the hooks of bungee cords may tangle with each other and with the cords when stored together in bin. To help prevent this, some bungee-cord designs permit the hooks to interlock or nest together for storage.
Many S and C hooks, as well as snap hooks and carabiners, do not provide an adequate grip to hold onto when stretching a bungee cord. A bungee cord that recoils when a user loses his grip may cause injury. Additionally, a user's finger may be pinched between a hook and an object if he pulls on the hook by curling his finger around it. Consequently, some hook designs have a pull tab on the shank that can be gripped with a finger.
Finally, a notable limitation of standard S and C hooks is that they may detach from an object due to slack in the cord, shifting of an object, or vibrations. Hooks such as carabiners and snap hooks address this limitation by providing a pivoting or sliding gate that creates an enclosed loop. The gate of such a hook may pivot within the plane of the hook inwardly or outwardly; the gate may pivot above or below the plane of the hook; or the gate may slide or translate. The gate may be biased by a spring, magnet, flexible member, and so on. The gate may be a stout straight member or the gate may resemble a hook itself, for example in clasps that comprise two opposing parallel contacting jaws that pivot about a shared joint.
Hook assemblies comprising parallel contacting opposing jaws may include one or more stop mechanisms to prevent one jaw from rotating beyond some angle relative to the other jaw. Such hook assemblies may also include one or more retention mechanisms to retain the hook assembly in a closed or opened position. A retention mechanism may be a bump or ridge on the surface of one jaw that engages with a dimple or notch on a surface of the other jaw.
Four issues of hook devices have been described above: (1) a hook having either too deep too shallow of a throat; (2) a hook tangling with cords and other hooks; (3) a hook lacking an adequate grip; and (4) a hook accidentally detaching from an object. This disclosure teaches an improved hook assembly that addresses one or more of these issues.